Intensity Modulated Radiation Therapy — CPB 0590 | AETNA Coverage Update

Aetna modified CPB 0590 for intensity modulated radiation therapy (IMRT), effective December 4, 2025. Here's what billing teams need to know.

Aetna, a CVS Health company, updated its IMRT coverage policy under CPB 0590 in the Aetna system, confirming medical necessity criteria for IMRT delivery, fiducial marker placement, and image guidance systems. The change directly affects nine CPT codes and six HCPCS codes, including 77301, 77385, 77386, 77387, and G6015. If your practice bills radiation oncology for Aetna members, audit your charge capture and documentation workflows now.

Quick-Reference Table

Aetna IMRT Coverage Criteria and Medical Necessity Requirements 2025

Aetna's IMRT coverage policy under CPB 0590 ties medical necessity directly to eviCore Healthcare's Radiation Therapy Clinical Guidelines. Aetna does not publish a standalone criteria list inside the bulletin itself. The criteria live at eviCore's site, and eviCore can update them without prior notice.

That's the first thing your billing team needs to understand. You're not working off a static Aetna document. You're working off guidelines that can change between annual reviews — and eviCore only guarantees 90 days of advance notice on draft updates. Build a process to check the eviCore guidelines page regularly, not just when a denial hits.

The core medical necessity standard for IMRT under CPB 0590 is this: critical structures cannot be adequately protected with standard 3-dimensional (3D) conformal radiotherapy. IMRT is not a first-line default for all cancer cases. The clinical rationale for choosing IMRT over 3D conformal RT must be documented before you submit CPT 77385 (simple delivery) or 77386 (complex delivery).

Fiducial Marker Placement

Aetna covers fiducial marker placement — billed under CPT 32553, 49327, 49411, or 49412, depending on the anatomical site and approach — when two additional conditions are met. First, the radiation target must not be clearly visible. Second, bony anatomy must not be sufficient for adequate target alignment. Both conditions are required. Missing documentation on either point is a fast path to a claim denial.

HCPCS codes A4648 (implantable tissue marker) and C1739 (imaging and non-imaging implantable device) cover the markers themselves. C9728 covers placement in facility outpatient settings. Know which code applies to your site of service before you bill.

Image Guidance Systems

Aetna covers both inter-fraction image guidance (between treatment sessions) and intra-fraction image guidance (real-time, within a session). The policy explicitly names the Calypso 4D Localization System and the RayPilot System as covered intra-fraction systems. CPT 77387 and HCPCS G6017 are the relevant billing codes for these services.

Prior authorization is almost certain to be required for IMRT given its routing through eviCore. Confirm your prior auth workflow is set up for eviCore, not Aetna directly — that's a common point of failure that causes delayed authorization and downstream reimbursement problems.

Coverage Indications at a Glance

Aetna IMRT Billing Guidelines and Action Items 2025

The effective date of December 4, 2025 is already here. If you haven't reviewed your IMRT billing workflows against the updated CPB 0590, do it now.

If your practice has a high volume of Aetna IMRT cases, loop in your compliance officer before the December 4, 2025 effective date to review your documentation templates against the current eviCore criteria. The financial exposure on IMRT claims is significant enough that this warrants a formal internal review.

CPT, HCPCS, and ICD-10 Codes for IMRT Under CPB 0590

Covered CPT Codes (When Selection Criteria Are Met)

Covered HCPCS Codes (When Selection Criteria Are Met)

Key ICD-10-CM Diagnosis Codes

The ICD-10 coverage spans the entire neoplasm chapter — C00.0 through D49.9 — which is broad. Aetna's limitation comes from the eviCore medical necessity criteria, not the diagnosis code range. A covered diagnosis does not automatically mean a covered claim. Clinical documentation and prior authorization carry the weight here.